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                                <div id="anchor-navigation-ex-navbar"><i class="fa fa-navicon"></i><ul><li><span class="title-icon "></span><a href="#&#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x7B97;&#x6CD5;&#x601D;&#x8DEF;"><b>1. </b>&#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x7B97;&#x6CD5;&#x601D;&#x8DEF;</a></li><ul><li><span class="title-icon "></span><a href="#&#x9010;&#x884C;&#x5206;&#x6790;&#x4F18;&#x5316;&#x7B97;&#x6CD5;"><b>1.1. </b>&#x9010;&#x884C;&#x5206;&#x6790;&#x4F18;&#x5316;&#x7B97;&#x6CD5;</a></li></ul></ul></div><h1 id="&#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x7B97;&#x6CD5;&#x601D;&#x8DEF;"><a name="&#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x7B97;&#x6CD5;&#x601D;&#x8DEF;" class="anchor-navigation-ex-anchor" href="#&#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x7B97;&#x6CD5;&#x601D;&#x8DEF;"><i class="fa fa-link" aria-hidden="true"></i></a>1. &#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x7B97;&#x6CD5;&#x601D;&#x8DEF;</h1>
<p>&#x6BCF;&#x6B21;&#x6267;&#x884C;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x524D;&#x90FD;&#x4F1A;&#x5148;&#x6E05;&#x7406;&#x6240;&#x6709;&#x4F9D;&#x8D56;&#x518D;&#x91CD;&#x65B0;&#x6536;&#x96C6;&#xFF0C;&#x4ECE;&#x800C;&#x51CF;&#x5C11;&#x65E0;&#x6548;&#x4F9D;&#x8D56;&#x7684;&#x89E6;&#x53D1;&#x3002;&#x4F46;&#x5982;&#x4E0B;&#x60C5;&#x51B5;&#xFF0C;&#x8FD9;&#x79CD;&#x6E05;&#x7406;&#x5DE5;&#x4F5C;&#x53CD;&#x800C;&#x589E;&#x52A0;&#x65E0;&#x8C13;&#x7684;&#x6027;&#x80FD;&#x6D88;&#x8017;</p>
<pre><code class="lang-ts"><span class="hljs-keyword">const</span> state = reactive({ show: <span class="hljs-literal">true</span>, values: [<span class="hljs-number">1</span>,<span class="hljs-number">2</span>,<span class="hljs-number">3</span>] })
effect(() =&gt; {
  <span class="hljs-built_in">console</span>.log(state.values)
})
</code></pre>
<p>&#x90A3;&#x4E48;&#x5E94;&#x8BE5;&#x5982;&#x4F55;&#x5904;&#x7406;&#x5462;&#xFF1F;@vue/reactivity&#x5DF2;&#x7ECF;&#x4E3A;&#x6211;&#x4EEC;&#x63D0;&#x4F9B;&#x4E86;&#x4E00;&#x4E2A;&#x975E;&#x5E38;&#x4F18;&#x79C0;&#x7684;&#x89E3;&#x51B3;&#x65B9;&#x6848;&#xFF0C;&#x8BF7;&#x770B;&#x4E0B;&#x9762;&#x5427;&#x3002;</p>
<h2 id="&#x9010;&#x884C;&#x5206;&#x6790;&#x4F18;&#x5316;&#x7B97;&#x6CD5;"><a name="&#x9010;&#x884C;&#x5206;&#x6790;&#x4F18;&#x5316;&#x7B97;&#x6CD5;" class="anchor-navigation-ex-anchor" href="#&#x9010;&#x884C;&#x5206;&#x6790;&#x4F18;&#x5316;&#x7B97;&#x6CD5;"><i class="fa fa-link" aria-hidden="true"></i></a>1.1. &#x9010;&#x884C;&#x5206;&#x6790;&#x4F18;&#x5316;&#x7B97;&#x6CD5;</h2>
<pre><code class="lang-ts"><span class="hljs-keyword">export</span> <span class="hljs-keyword">type</span> Dep = Set&lt;ReactiveEffect&gt; &amp; TrackedMarkers

<span class="hljs-keyword">type</span> TrackedMarkers = {
  <span class="hljs-comment">/**
   * wasTracked&#x7684;&#x7F29;&#x5199;&#xFF0C;&#x91C7;&#x7528;&#x4E8C;&#x8FDB;&#x5236;&#x683C;&#x5F0F;&#xFF0C;&#x6BCF;&#x4E00;&#x4F4D;&#x8868;&#x793A;&#x4E0D;&#x540C;effect&#x5D4C;&#x5957;&#x5C42;&#x7EA7;&#x4E2D;&#xFF0C;&#x8BE5;&#x4F9D;&#x8D56;&#x662F;&#x5426;&#x5DF2;&#x88AB;&#x8DDF;&#x8E2A;&#x8FC7;(&#x5373;&#x5728;&#x4E0A;&#x4E00;&#x8F6E;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6267;&#x884C;&#x65F6;&#x5DF2;&#x7ECF;&#x88AB;&#x8BBF;&#x95EE;&#x8FC7;)
   */</span> 
  w: <span class="hljs-built_in">number</span>
  <span class="hljs-comment">/**
   * newTracked&#x7684;&#x7F29;&#x5199;&#xFF0C;&#x91C7;&#x7528;&#x4E8C;&#x8FDB;&#x5236;&#x683C;&#x5F0F;&#xFF0C;&#x6BCF;&#x4E00;&#x4F4D;&#x8868;&#x793A;&#x4E0D;&#x540C;effect&#x5D4C;&#x5957;&#x5C42;&#x7EA7;&#x4E2D;&#xFF0C;&#x8BE5;&#x4F9D;&#x8D56;&#x662F;&#x5426;&#x4E3A;&#x65B0;&#x589E;(&#x5373;&#x5728;&#x672C;&#x8F6E;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6267;&#x884C;&#x4E2D;&#x88AB;&#x8BBF;&#x95EE;&#x8FC7;)
   */</span> 
  n: <span class="hljs-built_in">number</span>
}

<span class="hljs-keyword">export</span> <span class="hljs-keyword">const</span> createDep = (effects) =&gt; {
  <span class="hljs-keyword">const</span> dep = <span class="hljs-keyword">new</span> Set&lt;ReactiveEffect&gt;(effects) as Dep
  <span class="hljs-comment">// &#x867D;&#x7136;TrackedMarkers&#x6807;&#x8BC6;&#x662F;&#x4F4D;&#x4E8E;&#x54CD;&#x5E94;&#x5F0F;&#x5BF9;&#x8C61;&#x5C5E;&#x6027;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x4E0A;&#xFF0C;&#x4F46;&#x5B83;&#x6BCF;&#x4E00;&#x4F4D;&#x4EC5;&#x7528;&#x4E8E;&#x8868;&#x793A;&#x5F53;&#x524D;&#x6267;&#x884C;&#x7684;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x662F;&#x5426;&#x66FE;&#x7ECF;&#x8BBF;&#x95EE;&#x548C;&#x6B63;&#x5728;&#x8BBF;&#x95EE;&#x8BE5;&#x54CD;&#x5E94;&#x5F0F;&#x5BF9;&#x8C61;&#x5C5E;&#x6027;</span>
  dep.w = <span class="hljs-number">0</span>
  dep.n = <span class="hljs-number">0</span>

  <span class="hljs-keyword">return</span> dep
}

<span class="hljs-keyword">export</span> <span class="hljs-keyword">const</span> wasTracked = (dep: Dep): <span class="hljs-built_in">boolean</span> =&gt; (dep.w &amp; trackOpBit) &gt; <span class="hljs-number">0</span>

<span class="hljs-keyword">export</span> <span class="hljs-keyword">const</span> newTracked = (dep: Dep): <span class="hljs-built_in">boolean</span> =&gt; (dep.n &amp; trackOpBit) &gt; <span class="hljs-number">0</span>

<span class="hljs-comment">/**
 * &#x5C06;&#x5F53;&#x524D;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x7684;&#x4F9D;&#x8D56;&#x6807;&#x8BB0;&#x4E3A; `&#x5DF2;&#x7ECF;&#x88AB;&#x6536;&#x96C6;`
 */</span>
<span class="hljs-keyword">export</span> <span class="hljs-keyword">const</span> initDepMarkers = ({ deps }: ReactiveEffect) =&gt; {
  <span class="hljs-keyword">if</span> (deps.length) {
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; deps.length; i++) {
      deps[i].w |= trackOpBit
    }
  }
}

<span class="hljs-comment">/**
 * &#x7528;&#x4E8E;&#x5BF9;&#x66FE;&#x7ECF;&#x8DDF;&#x8E2A;&#x8FC7;&#xFF0C;&#x4F46;&#x672C;&#x6B21;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6267;&#x884C;&#x65F6;&#x6CA1;&#x6709;&#x8DDF;&#x8E2A;&#x7684;&#x4F9D;&#x8D56;&#xFF0C;&#x91C7;&#x53D6;&#x5220;&#x9664;&#x64CD;&#x4F5C;&#x3002;
 * &#x5373;&#xFF0C;&#x65B0;&#x8DDF;&#x8E2A;&#x7684; &#x548C; &#x672C;&#x8F6E;&#x8DDF;&#x8E2A;&#x8FC7;&#x7684;&#x90FD;&#x4F1A;&#x88AB;&#x4FDD;&#x7559;&#x3002;
 */</span>
<span class="hljs-keyword">export</span> <span class="hljs-keyword">const</span> finalizeDepMarkers = (effect: ReactiveEffect) =&gt; {
  <span class="hljs-keyword">const</span> { deps } = effect
  <span class="hljs-keyword">if</span> (deps.length) {
    <span class="hljs-keyword">let</span> ptr = <span class="hljs-number">0</span>
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; deps.length; i++) {
      <span class="hljs-keyword">const</span> dep = deps[i]
      <span class="hljs-keyword">if</span> (wasTracked(dep) &amp;&amp; !newTracked(dep)) {
        <span class="hljs-comment">// &#x5BF9;&#x4E8E;&#x66FE;&#x7ECF;&#x8DDF;&#x8E2A;&#x8FC7;&#xFF0C;&#x4F46;&#x672C;&#x6B21;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6267;&#x884C;&#x65F6;&#x6CA1;&#x6709;&#x8DDF;&#x8E2A;&#x7684;&#x4F9D;&#x8D56;&#xFF0C;&#x91C7;&#x53D6;&#x5220;&#x9664;&#x64CD;&#x4F5C;&#x3002;</span>
        dep.delete(effect)
      }
      <span class="hljs-keyword">else</span> {
        <span class="hljs-comment">// &#x7F29;&#x5C0F;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x7684;&#x5927;&#x5C0F;</span>
        deps[ptr++] = dep
      }
      <span class="hljs-comment">// &#x5C06;w&#x548C;n&#x4E2D;&#x5BF9;&#x5E94;&#x7684;&#x5D4C;&#x5957;&#x5C42;&#x7EA7;&#x7684;&#x4E8C;&#x8FDB;&#x5236;&#x4F4D;&#x7F6E;&#x96F6;&#xFF0C;&#x5982;&#x679C;&#x7F3A;&#x5C11;&#x8FD9;&#x6B65;&#x540E;&#x7EED;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x91CD;&#x65B0;&#x6267;&#x884C;&#x65F6;&#x5219;&#x65E0;&#x6CD5;&#x91CD;&#x65B0;&#x6536;&#x96C6;&#x4F9D;&#x8D56;&#x3002;</span>
      dep.w &amp;= ~trackOpBit
      dep.n &amp;= ~trackOpBit
    }
    <span class="hljs-comment">// &#x7F29;&#x5C0F;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x7684;&#x5927;&#x5C0F;</span>
    deps.length = ptr
  }
}
</code></pre>
<pre><code class="lang-ts"><span class="hljs-comment">// &#x5728;&#x4F4D;&#x4E8E;&#x54CD;&#x5E94;&#x5F0F;&#x4E0A;&#x4E0B;&#x6587;&#x6267;&#x884C;&#x7684;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x5185;&#xFF0C;&#x8BBF;&#x95EE;&#x54CD;&#x5E94;&#x5F0F;&#x5BF9;&#x8C61;&#x5C5E;&#x6027;&#xFF0C;&#x5C06;&#x901A;&#x8FC7;track&#x6536;&#x96C6;&#x4F9D;&#x8D56;</span>
<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">track</span>(<span class="hljs-params">target: object, <span class="hljs-keyword">type</span>: TrackOpTypes, key: unknown</span>) </span>{
  <span class="hljs-keyword">if</span> (!isTracking()) {
    <span class="hljs-keyword">return</span>
  }

  <span class="hljs-comment">// targetMap&#x7528;&#x4E8E;&#x5B58;&#x50A8;&#x54CD;&#x5E94;&#x5F0F;&#x5BF9;&#x8C61;-&#x5BF9;&#x8C61;&#x5C5E;&#x6027;&#x7684;&#x952E;&#x503C;&#x5BF9;</span>
  <span class="hljs-comment">// depsMap&#x7528;&#x4E8E;&#x5B58;&#x50A8;&#x5BF9;&#x8C61;&#x5C5E;&#x6027;-&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x96C6;&#x5408;&#x7684;&#x952E;&#x503C;&#x5BF9;</span>
  <span class="hljs-keyword">let</span> depsMap = targetMap.get(target)
  <span class="hljs-keyword">if</span> (!depsMap) {
    target.set(target, (depsMap = <span class="hljs-keyword">new</span> Map()))
  }
  <span class="hljs-keyword">let</span> dep = depsMap.get(key)
  <span class="hljs-keyword">if</span> (!dep) {
    depsMap.set(key, (dep = createDep()))
  }

  trackEffects(dep)
}

<span class="hljs-comment">// &#x6536;&#x96C6;&#x4F9D;&#x8D56;</span>
<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">trackEffects</span>(<span class="hljs-params">
  dep: Dep
</span>) </span>{
  <span class="hljs-keyword">let</span> shouldTrack = <span class="hljs-literal">false</span>
  <span class="hljs-keyword">if</span> (effectTrackDepth &lt;= maxMarkerBits) {
    <span class="hljs-comment">// &#x5982;&#x679C;&#x672C;&#x8F6E;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6267;&#x884C;&#x8FC7;&#x7A0B;&#x4E2D;&#x5DF2;&#x7ECF;&#x8BBF;&#x95EE;&#x5E76;&#x6536;&#x96C6;&#x8FC7;&#xFF0C;&#x5219;&#x4E0D;&#x7528;&#x518D;&#x6536;&#x96C6;&#x8BE5;&#x4F9D;&#x8D56;</span>
    <span class="hljs-keyword">if</span> (!newTracked(dep)) {
      dep.n |= trackOpBit
      shouldTrack = !wasTracked(dep)
    }
  }
  <span class="hljs-keyword">else</span> {
    <span class="hljs-comment">// &#x5BF9;&#x4E8E;&#x5168;&#x9762;&#x6E05;&#x7406;&#x7684;&#x60C5;&#x51B5;&#xFF0C;&#x5982;&#x679C;&#x5F53;&#x524D;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x5BF9;&#x5E94;&#x7684;ReactiveEffect&#x5BF9;&#x8C61;&#x4E0D;&#x5728;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x4E2D;&#xFF0C;&#x5219;&#x6807;&#x8BB0;&#x4E3A;true</span>
    shouldTrack = !dep.has(activeEffect!)
  }

  <span class="hljs-keyword">if</span> (shouldTrack) {
    dep.add(activeEffect!)
    activeEffect!.deps.push(dep)
  }
}
</code></pre>
<p>&#x5355;&#x5355;&#x4ECE;&#x4EE3;&#x7801;&#x5B9E;&#x73B0;&#x89D2;&#x5EA6;&#x80FD;&#x96BE;&#x7406;&#x89E3;&#x8FD9;&#x4E2A;&#x4F18;&#x5316;&#x65B9;&#x5F0F;&#xFF0C;&#x4E0D;&#x5982;&#x6211;&#x4EEC;&#x4ECE;&#x5B9E;&#x9645;&#x7684;&#x4F8B;&#x5B50;&#x51FA;&#x53D1;&#x5427;&#xFF01;</p>
<pre><code class="lang-ts"><span class="hljs-keyword">const</span> runAsync = fn =&gt; setTimeout(fn, <span class="hljs-number">1000</span>)

<span class="hljs-keyword">const</span> state = reactive({ show: <span class="hljs-literal">true</span>, values: [<span class="hljs-number">1</span>,<span class="hljs-number">2</span>,<span class="hljs-number">3</span>] })
<span class="hljs-comment">// 1</span>
effect(() =&gt; {
  <span class="hljs-keyword">if</span> (state.show) {
    <span class="hljs-built_in">console</span>.log(state.values)
  }
})

<span class="hljs-comment">// 2</span>
runAsync(() =&gt; {
  state.values.push(<span class="hljs-number">4</span>)
})

<span class="hljs-comment">// 3</span>
runAsync(() =&gt; {
  state.show = <span class="hljs-literal">false</span>
})
</code></pre>
<ol>
<li>&#x9996;&#x6B21;&#x6267;&#x884C;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;
a. <code>effectTrackDepth</code>&#x4E3A;0&#xFF0C;&#x56E0;&#x6B64;<code>1 &lt;&lt; ++effectTrackDepth</code>&#x5F97;&#x5230;&#x7684;<code>effectTrackDepth</code>&#x548C;<code>trackOpBit</code>&#x5747;&#x4E3A;1&#xFF0C;&#x4F46;&#x7531;&#x4E8E;&#x6B64;&#x65F6;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x8FD8;&#x6CA1;&#x6709;&#x6536;&#x96C6;&#x4F9D;&#x8D56;&#xFF0C;&#x56E0;&#x6B64;<code>initDepMarkers</code>&#x51FD;&#x6570;&#x6CA1;&#x6709;&#x4EFB;&#x4F55;&#x6548;&#x679C;&#xFF1B;
b. &#x8BBF;&#x95EE;<code>state.show</code>&#x65F6;&#x7531;&#x4E8E;&#x4E4B;&#x524D;&#x6CA1;&#x6709;&#x6536;&#x96C6;&#x8FC7;&#x54CD;&#x5E94;&#x5F0F;&#x5BF9;&#x8C61;<code>state</code>&#x7684;<code>show</code>&#x5C5E;&#x6027;&#xFF0C;&#x56E0;&#x6B64;&#x4F1A;&#x8C03;&#x7528;<code>createDep</code>&#x521B;&#x5EFA;<code>w</code>&#x548C;<code>n</code>&#x5747;&#x4E3A;0&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#xFF0C;&#x5E76;&#x8C03;&#x7528;<code>trackEffects</code>&#x53D1;&#x73B0;<code>newTracked(dep)</code>&#x4E3A;&#x672A;&#x8DDF;&#x8E2A;&#x8FC7;&#xFF0C;&#x5219;&#x5C06;<code>n</code>&#x8BBE;&#x7F6E;&#x4E3A;1&#xFF0C;&#x7136;&#x540E;&#x5F00;&#x59CB;&#x6536;&#x96C6;&#x4F9D;&#x8D56;&#xFF1B;
c. &#x8BBF;&#x95EE;<code>state.values</code>&#x4F1A;&#x91CD;&#x590D;&#x7B2C;2&#x6B65;&#x7684;&#x64CD;&#x4F5C;&#xFF1B;
d. &#x7531;&#x4E8E;<code>state.show</code>&#x548C;<code>state.values</code>&#x90FD;&#x662F;&#x65B0;&#x8DDF;&#x8E2A;&#x7684;(<code>n</code>&#x4E3A;1)&#xFF0C;&#x56E0;&#x6B64;&#x5728;<code>finalizeDepMarkers</code>&#x5904;&#x7406;&#x540E;&#x4ECD;&#x7136;&#x5C06;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x4FDD;&#x7559;&#x5728;&#x8FD9;&#x4E24;&#x4E2A;&#x5C5E;&#x6027;&#x5BF9;&#x5E94;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x4E2D;&#x3002;</li>
<li>&#x6267;&#x884C;<code>state.values.push(4)</code>&#x89E6;&#x53D1;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x53D8;&#x5316;
a. <code>effectTrackDepth</code>&#x4E3A;0&#xFF0C;&#x56E0;&#x6B64;<code>1 &lt;&lt; ++effectTrackDepth</code>&#x5F97;&#x5230;&#x7684;<code>effectTrackDepth</code>&#x548C;<code>trackOpBit</code>&#x5747;&#x4E3A;1&#xFF0C;&#x6B64;&#x65F6;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x5DF2;&#x7ECF;&#x6536;&#x96C6;&#x8FC7;&#x4F9D;&#x8D56;&#xFF0C;&#x56E0;&#x6B64;<code>initDepMarkers</code>&#x5C06;&#x8BE5;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6240;&#x5728;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x90FD;&#x90FD;&#x6807;&#x8BB0;&#x4E3A;&#x5DF2;&#x6536;&#x96C6;&#x8FC7;(<code>w</code>&#x4E3A;1)&#xFF1B;
b. &#x8BBF;&#x95EE;<code>state.show</code>&#x65F6;&#x4F1A;&#x8C03;&#x7528;<code>trackEffects</code>&#x53D1;&#x73B0;<code>newTracked(dep)</code>&#x4E3A;&#x672A;&#x8DDF;&#x8E2A;&#x8FC7;(&#x5728;<code>finalizeDepMarkers</code>&#x4E2D;&#x5DF2;&#x88AB;&#x7F6E;&#x96F6;)&#xFF0C;&#x5219;&#x5C06;<code>n</code>&#x8BBE;&#x7F6E;&#x4E3A;1&#xFF0C;&#x7136;&#x540E;&#x5F00;&#x59CB;&#x6536;&#x96C6;&#x4F9D;&#x8D56;&#xFF1B;
c. &#x8BBF;&#x95EE;<code>state.values</code>&#x4F1A;&#x91CD;&#x590D;&#x7B2C;2&#x6B65;&#x7684;&#x64CD;&#x4F5C;&#xFF1B;
d. &#x7531;&#x4E8E;<code>state.show</code>&#x548C;<code>state.values</code>&#x90FD;&#x662F;&#x65B0;&#x8DDF;&#x8E2A;&#x7684;(<code>n</code>&#x4E3A;1)&#xFF0C;&#x56E0;&#x6B64;&#x5728;<code>finalizeDepMarkers</code>&#x5904;&#x7406;&#x540E;&#x4ECD;&#x7136;&#x5C06;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x4FDD;&#x7559;&#x5728;&#x8FD9;&#x4E24;&#x4E2A;&#x5C5E;&#x6027;&#x5BF9;&#x5E94;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x4E2D;&#x3002;</li>
<li>&#x6267;&#x884C;<code>state.show = false</code>&#x89E6;&#x53D1;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x53D8;&#x5316;
a. <code>effectTrackDepth</code>&#x4E3A;0&#xFF0C;&#x56E0;&#x6B64;<code>1 &lt;&lt; ++effectTrackDepth</code>&#x5F97;&#x5230;&#x7684;<code>effectTrackDepth</code>&#x548C;<code>trackOpBit</code>&#x5747;&#x4E3A;1&#xFF0C;&#x6B64;&#x65F6;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x5DF2;&#x7ECF;&#x6536;&#x96C6;&#x8FC7;&#x4F9D;&#x8D56;&#xFF0C;&#x56E0;&#x6B64;<code>initDepMarkers</code>&#x5C06;&#x8BE5;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x6240;&#x5728;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x90FD;&#x90FD;&#x6807;&#x8BB0;&#x4E3A;&#x5DF2;&#x6536;&#x96C6;&#x8FC7;(<code>w</code>&#x4E3A;1)&#xFF1B;
b. &#x8BBF;&#x95EE;<code>state.show</code>&#x65F6;&#x4F1A;&#x8C03;&#x7528;<code>trackEffects</code>&#x53D1;&#x73B0;<code>newTracked(dep)</code>&#x4E3A;&#x672A;&#x8DDF;&#x8E2A;&#x8FC7;(&#x5728;<code>finalizeDepMarkers</code>&#x4E2D;&#x5DF2;&#x88AB;&#x7F6E;&#x96F6;)&#xFF0C;&#x5219;&#x5C06;<code>n</code>&#x8BBE;&#x7F6E;&#x4E3A;1&#xFF0C;&#x7136;&#x540E;&#x5F00;&#x59CB;&#x6536;&#x96C6;&#x4F9D;&#x8D56;&#xFF1B;
c. &#x7531;&#x4E8E;<code>state.values</code>&#x6CA1;&#x6709;&#x6807;&#x8BB0;&#x4E3A;&#x65B0;&#x8DDF;&#x8E2A;&#x7684;(<code>n</code>&#x4E3A;0)&#xFF0C;&#x56E0;&#x6B64;&#x5728;<code>finalizeDepMarkers</code>&#x5904;&#x7406;&#x540E;&#x4F1A;&#x5C06;&#x526F;&#x4F5C;&#x7528;&#x51FD;&#x6570;&#x4ECE;<code>state.values</code>&#x5BF9;&#x5E94;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x4E2D;&#x79FB;&#x9664;&#xFF0C;&#x4EC5;&#x4FDD;&#x7559;&#x5728;<code>state.values</code>&#x5BF9;&#x5E94;&#x7684;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x4E2D;&#x3002;</li>
</ol>
<p>@vue/reactivity&#x7ED9;&#x6211;&#x4EEC;&#x5C55;&#x793A;&#x4E86;&#x4E00;&#x4E2A;&#x975E;&#x5E38;&#x4F18;&#x79C0;&#x7684;&#x5904;&#x7406;&#x65B9;&#x5F0F;&#xFF0C;&#x90A3;&#x4E48;&#x5C31;&#x662F;&#x901A;&#x8FC7;&#x6807;&#x8BC6;&#x6BCF;&#x4E2A;&#x4F9D;&#x8D56;&#x96C6;&#x5408;&#x7684;&#x72B6;&#x6001;(&#x65B0;&#x4F9D;&#x8D56;&#x548C;&#x5DF2;&#x7ECF;&#x88AB;&#x6536;&#x96C6;&#x8FC7;)&#xFF0C;&#x5E76;&#x5BF9;&#x65B0;&#x4F9D;&#x8D56;&#x548C;&#x5DF2;&#x7ECF;&#x88AB;&#x6536;&#x96C6;&#x8FC7;&#x4E24;&#x4E2A;&#x6807;&#x8BC6;&#x8FDB;&#x884C;&#x5BF9;&#x6BD4;&#x7B5B;&#x9009;&#x51FA;&#x5DF2;&#x88AB;&#x5220;&#x9664;&#x7684;&#x4F9D;&#x8D56;&#x9879;&#x3002;</p>
<p>&#x5230;&#x8FD9;&#x91CC;&#xFF0C;&#x6211;&#x60F3;&#x5927;&#x5BB6;&#x5DF2;&#x7ECF;&#x5BF9;&#x8FD9;&#x4E2A;&#x4F18;&#x5316;&#x6709;&#x66F4;&#x6DF1;&#x7684;&#x7406;&#x89E3;&#x4E86;&#x3002;&#x90A3;&#x4E48;&#x63A5;&#x4E0B;&#x6765;&#x7684;&#x95EE;&#x9898;&#x81EA;&#x7136;&#x800C;&#x7136;&#x5C31;&#x662F;&#x4E3A;&#x4EC0;&#x4E48;&#x8981;&#x786C;&#x7F16;&#x7801;&#x5C06;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x542F;&#x52A8;&#x7684;&#x5D4C;&#x5957;&#x5C42;&#x7EA7;&#x8BBE;&#x7F6E;&#x4E3A;<code>maxMarkerBits = 30</code>&#xFF1F;
&#x8BF7;&#x770B;&#x4E0B;&#x4E00;&#x8282;<a href="5_smi.html">&#x300A;&#x4F9D;&#x8D56;&#x6E05;&#x7406;&#x4F18;&#x5316;&#x7B97;&#x6CD5;&#x8BE6;&#x89E3;-&#x57FA;&#x4E8E;JavaScript&#x5F15;&#x64CE;&#x7684;SMI&#x8FDB;&#x4E00;&#x6B65;&#x538B;&#x69A8;&#x6027;&#x80FD;&#x300B;</a></p>
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